1. Field of the Invention
The present invention relates to a radical-modified polymer and a polymer composition containing the same. More specifically, it relates to a radical-modified polymer having, at the end of the molecule or in the molecular chain thereof, a free radical stable in the presence of oxygen at an ordinary temperature and a polymer composition containing the same.
2. Description of the Related Art
Introduction of a stable free radical TEMPO (i.e., tetramethyl piperidinyloxy) compound at the end of the molecule or in the molecular chain of a polyester or polyether has, for example, been reported in the Japanese Journal of Polymer Science and Technology, vol. 57, no. 8 (2000). However, when using a TEMPO compound as a radical for a growing chain end radical in living radical polymerization of a diene monomer for polymerizing the diene monomer, a diene polymer having a free radical stably bonded in the free state at the end of the polymer produced has not been obtained yet. Among the TEMPO compounds used, those having a diene polymer as the substituent group have been described in, for example, Japanese Unexamined Patent Publication (Kokai) No. 2000-109512, Japanese Unexamined Patent Publication (Kokai) No. 1998-045817, etc. However, the use of these polymers for a polymer formulation is not described therein. Note that a rubber composition containing a free radical compound having a radical such as a nitroxide radical, hydroxy radical in the rubber has been proposed in, for example, Japanese Unexamined Patent Publication (Kokai) No. 10-182881.
An object of the present invention is to provide a polymer having a stable free radical compound introduced at the end of the molecule or in the molecular chain thereof, a block and/or graft copolymer obtained by reacting the radical induced polymer with a polymer capable of generating a radical on the molecular chain thereof, and a polymer composition containing the same having excellent abrasion resistance and mechanical strength, etc.
In accordance with the present invention, there is provided a radical-modified polymer having a free radical compound stable in the presence of oxygen at an ordinary temperature at the end of the molecule or in the molecular chain thereof.
In accordance with the present invention, there is also provided a polymer composition comprising a block and/or graft copolymer of a radical-modified polymer obtained by mixing (i) the above-mentioned radical-modified polymer and (ii) a polymer capable of generating a radical on the molecule thereof.